Throw your XP at yourself (e.g. to repair your mending tools)
Save your XP to a sign
Automatically close doors after they have been opened
Prevent loosing all your XP after death
Teleport players between signs without using any command
Let mobs talk to players on events like damage or death
Let mobs explode once they die
Transfer and sort items from inventories like chests into other inventories
Send chat messages from/to MatterBridge